Patents Examined by Lawrence B. Williams
  • Patent number: 8218674
    Abstract: A multi-antenna transmitter includes an adaptive bit interleaver for orthogonal frequency division multiplexed (OFDM) communications. The adaptive bit interleaver permutes a variable number of coded bits per OFDM symbol (Ncbps). The variable number of coded bits is calculated based on individual subcarrier modulation assignments for orthogonal subcarriers. The interleaver matrix size may be based on the variable number of coded bits per OFDM symbol and the number of subchannels. The interleaver may add padding bits to the interleaver matrix to fill any remaining positions, and after performing an interleaving operation, the interleaver may prune the padding bits to provide a sequence of interleaved bits for subsequent modulation on the orthogonal subcarriers and transmission by more than one antenna. The transmitter may transmit the OFDM symbol in accordance with an IEEE 802.16 standard.
    Type: Grant
    Filed: June 26, 2009
    Date of Patent: July 10, 2012
    Assignee: Intel Corporation
    Inventors: Alexander A. Maltsev, Ali S. Sadri, Alexei V. Davydov
  • Patent number: 8218680
    Abstract: A transmitting apparatus includes a modulation signal generating section that generates a modulation signal by modulating transmission data using one of a plurality of modulation schemes. The plurality of modulation schemes include a first modulation scheme, a second modulation scheme, and a third modulation scheme, where the first modulation scheme has maximum m-ary modulation value, the second modulation scheme has a lower m-ary modulation value than the first modulation scheme, and the third modulation scheme has a lower m-ary modulation value than the second modulation scheme. The transmitting apparatus also includes a pilot signal generating section that generates a pilot signal having one of a plurality of amplitudes, the pilot signal having a lower amplitude than a maximum amplitude of the first modulation scheme.
    Type: Grant
    Filed: April 25, 2011
    Date of Patent: July 10, 2012
    Assignee: Panasonic Corporation
    Inventors: Yutaka Murakami, Shinichiro Takabayashi, Katsuaki Abe, Masayuki Orihashi, Akihiko Matsuoka
  • Patent number: 8218701
    Abstract: A frame synchronization device and a frame synchronization method capable of preventing a malfunction when a frame is synchronized by using a frame synchronization pattern varying sequentially is presented. A bit serial signal at every frame is transmitted sequentially in a shift register composed of flip-flop circuits. When a bit in each of the stages is detected to be coincided with a corresponding bit in a frame synchronization pattern by coincidence circuits, existence of a synchronized frame is determined. Each bit in the synchronization pattern is also inputted into an all-zero detection circuit. If an all-zero state is detected, a first AND circuit does not output a synchronization pattern detecting signal even with a case where coincidence is detected from the coincidence circuits.
    Type: Grant
    Filed: March 18, 2008
    Date of Patent: July 10, 2012
    Assignee: NEC Corporation
    Inventor: Tsugio Takahashi
  • Patent number: 8213536
    Abstract: Systems and methods for reducing the peak-to-average ratio (PAR) at the transmitter can reduce the dynamic range required in various analog components. PAR can be reduced by applying a time-domain compensation signal which reduces the magnitude of peaks in the time-domain signal prior to transmission where the time-domain compensation signals use tones that are reserved for the purpose of reducing the PAR. The reservation of these reserved tones for PAR can be implemented by altering the typical startup procedures in a digital subscriber line (xDSL) system. The use of the reserved tones to reduce the PAR can be implemented using a low complexity algorithm or using an adaptive technique.
    Type: Grant
    Filed: June 13, 2008
    Date of Patent: July 3, 2012
    Assignee: Ikanos Communications, Inc.
    Inventors: Harish Jethanandani, Rahul Garg, Patrick Duvaut, Amitkumar Mahadevan
  • Patent number: 8213546
    Abstract: A method performed by a receiver is provided. The method includes generating an RDS/RBDS candidate codeword from a set of RDS/RBDS symbols where the RDS/RBDS candidate codeword has a subset of RDS/RBDS values that differs from corresponding subsets of RDS/RBDS values in all other possible RDS/RBDS codewords and determining whether the RDS/RBDS candidate codeword meets an acceptance criterion by comparing a first subset of reliability values determined from the set of RDS/RBDS symbols and having signs that differ from corresponding signs in the subset of RDS/RBDS values with a second subset of reliability values determined from the set of RDS/RBDS symbols and mutually exclusive with the first subset of the reliability values. A first number of values in the first and the second subsets of reliability values is less than a second number of values in the RDS/RBDS candidate codeword.
    Type: Grant
    Filed: November 13, 2007
    Date of Patent: July 3, 2012
    Assignee: Silicon Laboratories Inc.
    Inventor: Dana Taipale
  • Patent number: 8213550
    Abstract: Wideband digital receiver with integrated dynamic narrowband channelization and analysis. Signals received in a wide band are channelized into a plurality of narrower band channels within the wide band and input into a programmable narrowband filter. A set of descriptors is formed, each corresponding to an associated output signal of each of the channels. The descriptors are analyzed to determine if further processing is warranted. For each descriptor warranting further processing, one or more corresponding analysis algorithms is/are selected from a library of available analysis algorithms. The programmable narrowband filter is adjusted and a new descriptor is formed of its output. The initial set of descriptors is augmented with the new descriptor. The new descriptor is analyzed to determine if further processing of received signals is warranted.
    Type: Grant
    Filed: March 23, 2009
    Date of Patent: July 3, 2012
    Assignee: Lockheed Martin Corporation
    Inventor: Patrick Ballester
  • Patent number: 8213554
    Abstract: A method of signal processing, comprising: obtaining a digital signal (yn) based on another signal (xt) and noise; and estimating information relating to the another signal (xt) by using a denoising process to produce a denoised signal (y?n) and by processing the denoised signal (y?n), wherein the denoised signal (y?n) produced by the denoising process has a substantially Finite Rate of Innovation.
    Type: Grant
    Filed: June 13, 2008
    Date of Patent: July 3, 2012
    Assignee: QUALCOMM Incorporated
    Inventors: Thierry Blu, Martin Vetterli, Lionel Coulot
  • Patent number: 8213544
    Abstract: A digital broadcast receiver includes a tuner receiving a digital television (DTV) signal which includes a first data group including mobile service data, and the DTV signal has been processed by generating the first data group by interleaving a second data group by a DTV transmitter.
    Type: Grant
    Filed: September 21, 2010
    Date of Patent: July 3, 2012
    Assignee: LG Electronics Inc.
    Inventors: Byoung Gill Kim, In Hwan Choi, Jin Woo Kim, Jong Moon Kim, Won Gyu Song, Hyoung Gon Lee, Kook Yeon Kwak
  • Patent number: 8213527
    Abstract: A first wireless communication device recovers data from a transmission received over a wireless channel from a second wireless communication device and processes the received data with each of multiple channel variation compensations to produce corresponding processed received data subjected to respective ones of the multiple channel variation compensations. For symbols in the received data and in each of the processed received data, distances are computed to their closest symbols in a symbol constellation set used in the wireless transmission. A corresponding distance metric is computed from the distances for symbols in the received data and from the distances for symbols in each of the processed received data resulting in a distance metric for the received data, and a distance metric for each of the processed received data. Channel variation of a wireless channel between the first and second wireless communication devices is estimated based on the distance metrics.
    Type: Grant
    Filed: March 25, 2009
    Date of Patent: July 3, 2012
    Assignee: Cisco Technology, Inc.
    Inventors: Genyuan Wang, Hang Jin
  • Patent number: 8213541
    Abstract: A weight vector computing unit derives amounts of phase rotation for a plurality of multicarrier signals, respectively, and rotates the phase of a weight vector. A combining unit weights respectively a plurality of multicarrier signals with the phase-rotated weight vector, combines weighting results, and determines a combined result. A receiving weight vector computing unit remodulates the determined result and derives a first phase difference between the plurality of multicarrier signals and a result of the remodulation. The receiving weight vector computing unit remodulates the values of pilot signals and derives a second phase difference between the plurality of multicarrier signals and a result of the remodulation. Further, the receiving weight vector derives phase rotation amounts based on the first phase difference and the second phase difference.
    Type: Grant
    Filed: September 12, 2007
    Date of Patent: July 3, 2012
    Assignee: Hera Wireless S.A.
    Inventors: Seigo Nakao, Yoshiyuki Otani, Kiyoshige Ito
  • Patent number: 8208516
    Abstract: The disclosure is directed to an apparatus and method for encoder initialization and communications. The apparatus may include a database and an encoder module. The database may be configured to receive a plurality of parameters to be used for operation of the encoder module. The database may be further configured to store the plurality of parameters and to provide the plurality of parameters to the encoder module. The encoder module includes an encoder configured to be initialized based on the plurality of parameters from the database. When invoked, the encoder may rely on the database to initialize rather than performing measurements on the current signal that is to be encoded. In one aspect, the apparatus may be an access terminal that can seamlessly switch between different domains, different networks, different base stations, and different access points.
    Type: Grant
    Filed: July 9, 2007
    Date of Patent: June 26, 2012
    Assignee: Qualcomm Incorporated
    Inventors: Arnaud Meylan, Mark Whitney, Ranjith Jayaram
  • Patent number: 8160182
    Abstract: A symbol detector with a sphere decoding method implemented therein. A baseband signal is received to determine a maximum likelihood solution using the sphere decoding algorithm. A QR decomposer performs a QR decomposition process on a channel response matrix to generate a Q matrix and an R matrix. A matrix transformer generates an inner product matrix of the Q matrix and the received signal. A scheduler reorganizes a search tree, and takes a search mission apart into a plurality of independent branch missions, wherein the search tree defines a full search depth Nfull. A plurality of Euclidean distance calculators are controlled by the scheduler to operate in parallel, wherein each has a plurality of calculation units cascaded in a pipeline structure to search for the maximum likelihood solution based on the R matrix and the inner product matrix.
    Type: Grant
    Filed: March 24, 2009
    Date of Patent: April 17, 2012
    Assignee: Industrial Technology Research Institute
    Inventors: Chin-Hung Chen, Pang-An Ting, Cheng-Ming Chen, Chih-Yu Chen
  • Patent number: 8139673
    Abstract: A transmission method of a wireless signal including the following steps is provided. Multiple orthogonal frequency division multiplexing (OFDM) symbols carried by multiple subcarriers are generated according to a data signal. A scrambling pattern including multiple scrambling symbols is generated, wherein the scrambling symbols respectively correspond to the subcarriers in the frequency domain. The scrambling symbols corresponding to two contiguous subcarriers are correlated. The scrambling symbols are utilized to encode the OFDM symbols carried by the corresponding subcarriers.
    Type: Grant
    Filed: June 16, 2008
    Date of Patent: March 20, 2012
    Assignee: Industrial Technology Research Institute
    Inventors: Hsien-Wen Chang, Chorng-Ren Sheu, Ming-Chien Tseng, Ching-Yung Chen
  • Patent number: 8073042
    Abstract: A method and apparatus for detecting out-of-specification data streams and voltage controller oscillator operation. Data may be received over evaluation periods. Each evaluation period is segmented into n sub-periods. Each n sub-period has the same length. Each n sub-period spans a portion of the data. The corresponding data period starting at each of the n sub-period is evaluated. The sub-period interval counts may be stored in a first-in-first-out register.
    Type: Grant
    Filed: April 12, 2006
    Date of Patent: December 6, 2011
    Assignee: Cypress Semiconductor Corporation
    Inventor: Edward L. Grivna
  • Patent number: 8045669
    Abstract: In one aspect, a digital PLL (DPLL) operates based on fractional portions of input and output phases. The DPLL accumulates at least one input signal to obtain an input phase. The DPLL determines a fractional portion of an output phase based on a phase difference between an oscillator signal from an oscillator and a reference signal, e.g., using a time-to-digital converter (TDC). The DPLL determines a phase error based on the fractional portion of the input phase and the fractional portion of the output phase. The DPLL then generates a control signal for the oscillator based on the phase error. In another aspect, a DPLL includes a synthesized accumulator that determines a coarse output phase by keeping track of the number of oscillator signal cycles based on the reference signal.
    Type: Grant
    Filed: November 29, 2007
    Date of Patent: October 25, 2011
    Assignee: QUALCOMM Incorporated
    Inventors: Gary John Ballantyne, Bo Sun
  • Patent number: 8027417
    Abstract: A level of interference affecting signal components of received communication signals is estimated and used to weight the signal components. The signal components in a each of a number of groups of signal components are weighted based on respective interference estimates to thereby adjust signal components for colored interference, which may vary significantly between different groups of signal components. Each group of signal components may include a single component or components within a relatively narrow sub-band of the communication signals, such as a coherence bandwidth of an Orthogonal Frequency Division Multiplexing (OFDM) signal.
    Type: Grant
    Filed: December 19, 2003
    Date of Patent: September 27, 2011
    Assignee: Nortel Networks Limited
    Inventors: Ming Jia, Wen Tong, Dong-Shen Yu
  • Patent number: 8027388
    Abstract: One embodiment of the present invention relates to a method of transferring data in a communication system. In the method, an initial impulse noise protection value is determined. A number of redundancy bits is added to blocks of data to form codewords as a function of the initial impulse noise protection value, where the impulse noise protection value corresponds to a number of consecutive symbols that can be corrected. The number of symbols that can be correctly transmitted is changed by changing only the number of redundancy bits added to each block of data.
    Type: Grant
    Filed: January 21, 2011
    Date of Patent: September 27, 2011
    Assignee: Lantiq Deutschland, GmbH
    Inventors: Bernd Heise, Vladimir Oksman
  • Patent number: 8019024
    Abstract: Log-likelihood ratios are approximated for encoded bits modulated with a 2m-ary QAM constellation. Each symbol of the constellation is identified by a respective string of m bits. The log-likelihood ratio of each bit of the m bits is approximated with a product ? of a respective factor by a respective variable D that depends on a received signal and on communication channel characteristics. The approximating includes determining a value of at least one of the variables D using a parametric nonlinear function of an equalized replica z of a respective received signal.
    Type: Grant
    Filed: March 19, 2008
    Date of Patent: September 13, 2011
    Assignee: Dora S.p.A.
    Inventors: Lorenzo Guerrieri, Paola Bisaglia
  • Patent number: 8014470
    Abstract: Systems and methods are provided for decoding a signal vector in a transmission scheme that uses transmit diversity as well as HARQ, repetition coding, or any other protocol that allows a receiver to obtain multiple reception of common transmit information. Information obtained in more than one symbol period are treated as a single received vector, and each of the received signal vectors may be processed to reduce or remove phase rotations caused by the channel. The received signal vectors may be combined by addition and decoded using a maximum-likelihood decoder. In some embodiments, the transmitter and receiver are configured to communicate using the transmit diversity scheme and a spatial multiplexing scheme. The scheme may be chosen based on the quality of the channel through which communication takes place.
    Type: Grant
    Filed: September 12, 2007
    Date of Patent: September 6, 2011
    Assignee: Marvell World Trade Ltd.
    Inventors: Jungwon Lee, Woong Jun Jang
  • Patent number: 8009766
    Abstract: A digital television (DTV) receiving system includes a known data detector, and a channel impulse response (CIR) estimator, a CIR calculator, a coefficient calculator, and a multiplier. The known data detector detects positions of known data and field sync data included in a data group. The CIR estimator estimates CIRs of the data included in the data group using the detected positions of the field sync data and the known data. The CIR calculator performs interpolation or extrapolation based on a characteristic of each data region included in the data group. The coefficient calculator calculates equalization coefficients using the estimated CIRs, and the multiplier multiplies the data in the data group with the coefficients.
    Type: Grant
    Filed: July 6, 2007
    Date of Patent: August 30, 2011
    Assignee: LG Electronics Inc.
    Inventors: Byoung Gill Kim, In Hwan Choi, Jin Woo Kim, Jong Moon Kim, Won Gyu Song, Hyoung Gon Lee, Kook Yeon Kwak